In the state of the art, pre-launch testing of satellites, in particular their payloads, is known wherein several different tests are performed. It has been turned out that multipaction occurrence is a further test item that has to be performed during pre-launch testing of satellites wherein these tests are typically performed inside a thermal vacuum chamber (TVAC).
Multipaction (multipactor effect) is an electron resonance effect in vacuum conditions such as space when a local radio frequency field accelerates electrons such that these electrons impact with a surface. If the energy of these electrons is high enough, their collisions with the surface will lead to a release of so called secondary electrons. Each of the newly released secondary electrons follows the same pattern of the initial electron. Accordingly, this may result in an exponential rise of the number of electrons, in particular in case of a sustained multiplication, as secondary electron emission in resonance with an alternating electric field leads to an exponential multiplication of the electrons.
In radio frequency space systems, the multipactor effect may lead to the degradation of the radio frequency signal by increased noise that is generated by the secondary electrons. Further, damage to radio frequency components or subsystems of the space system will occur if local radio frequency power increases sufficiently since the number of electrons rise.
In general, the multipactor effect is a phenomenon that occurs in devices where high electrical field strength are common such as high power travelling wave tube amplifiers (TWTA), high power waveguides and waveguide components such as diplexers and filters. However, multipaction needs to be minimal and tested against margin.
During pre-launch testing of the satellite within the thermal vacuum chamber, the exponential rise of the number of electrons may cause an operational failure. In addition, the multipaction might damage or even destroy the radio frequency components of the satellite and/or the testing system.
Thus, there is a need for a testing method as well as a testing system that ensure proper work during the testing without damaging the testing components or the device under test.